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    <title>Document</title>
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    <script>
   //求出1-1/2+1/3-1/4…..1/100的和 var i=1;
    
    var n =0;
    var f =0;
    for(var j =1; j<=100;j++){
        if(j%2==0){
            n -= 1/j;
        }
        else{
            f += 1/j;
        }
    }
    console.log(n+f)


    </script>
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